Early on in a relationship the facade of civility keeps you in check, because you can't let the other person know how truly goddamn crazy you are until they're kinda stuck with dealing with you. Once you're there and know far too much about each other, the gloves are off and all bets are too. Your fights go from these happy passive aggressive little spats to violating terms of the Geneva convention.
Anyways, yeah. Here's some memes.